The present invention relates to the general field of turbine engines. It relates more particularly to detecting a rotating stall affecting a turbine engine compressor.
The invention applies to any type of turbine engine, and in particular to aeroengines such as turbojets, turboprops, etc.
In known manner, a rotating stall is an aerodynamic instability that affects the compressor and that is characterized by the presence of one or more localized pockets of fluid (referred to as stall pockets or cells) that propagate in the circumferential direction of the compressor, at a speed that is generally slower than the speed of rotation of the compressor.
As a general rule, this instability gives rise to a drop in compression characteristics and it is manifested in particular by a drop in the efficiency and in the compression ratio of the compressor. It is also responsible for major vibratory phenomena that can lead to premature wear of the blades in the compressor.
It can thus readily be understood that it is important to be able to detect the appearance of a rotating stall appearing in the compressor of a turbine engine both quickly and reliably.
In the present state of the art, numerous methods have been proposed in order to solve this problem. Nevertheless, most of these methods rely:                either on detection techniques that do not make it possible to distinguish between a surging situation and a rotating stall situation. This applies in particular to the method proposed in document U.S. Pat. No. 4,581,888;        or else on using sensors that are expensive and unusual in turbine engine, e.g. fast and high-performance pressure sensors as described in document U.S. Pat. No. 6,871,487.        
There thus exists a need for a simple, fast, and reliable solution for detecting a rotating stall, and that preferably relies on sensors that are already present in a turbine engine.